NOV. 22 , It)I 5 
Occurrence of Manganese in Wheat 
353 
Table IV .—Manganese in other grains 
Variety. 
Locality. 
Per cent. 
Emmer (Triticum dicoccum) . 
Rye ( Secale cereale) . 
Fort Collins, Colo. 
.do. 
0. 004 
. 004 
. 002 
. 005 
Barley, bald (Hordeum sp.). 
.do. 
Oats (Avena sativa) . 
.do. 
Several samples of corn (Zea mays) were tested, a large white variety 
(Meerschaum) from Missouri, a yellow variety, irrigated, from Grand 
Junction, Colo., a yellow variety, not irrigated, from Akron, Colo., and 
a white variety, irrigated, from Fort Collins, Colo. These samples con¬ 
tained so minute a trace of manganese that it could be detected only 
with great difficulty when 10 gm. of the grain were used for the test. 
In addition to the determinations of manganese given in the preceding 
tables, I have found it uniformly present in the ash of Colorado wheats 
and also in wheats from California, Nevada, Washington, Montana, 
South Dakota, Minnesota, Kentucky, and Tennessee. It can, I believe, 
be accepted as being universally present in the wheat kernel and like¬ 
wise in the wheat plant, but it is not as abundant in the dried plant as 
in the kernels. The ratio of the iron to manganese is higher in the plant. 
The risk of obtaining iron from dust, etc., in the case of the plant is, it 
is true, greater than in the case of the kernel, but I think that we are 
fairly safe in assuming that the iron found in our samples belongs to the 
plant constituents and is not derived from extraneous sources (Table V). 
Table V. —Iron and manganese in dried wheat plants 
Variety. 
Date. 
Fertilizer per acre. 
Iron. 
Manganese. 
Defiance. 
July 28, 1913.. 
.do. 
Aug. 6,1914. .. 
120 pounds of nitrogen. 
Per cent. 
Per cent. 
0. 004 
. 003 
. 003 
. 004 
. 004 
. 002 
Do. 
Do. 
Red Fife. 
Do. 
Kubanka. 
60 pounds of phosphorus. .. 
200 pounds of potassium. . . 
60 pounds of phosphorus... 
200 pounds of potassium. . . 
60 pounds of phosphorus. .. 
0. OIO 
. OIO 
. OIO 
.015 
. 008 
Do. 
.do. 
200 pounds of potassium, .. 
. 013 
. 002 
Of the preceding samples only the last two were ripe; the others were 
cut from 8 to 12 days before being ripe enough to harvest. 
The iron present in the straws is from two and one-half to six times as 
great in amount as the manganese, while in the kernels the manganese 
is approximately equal to the iron and at the same time is higher, as a 
rule, than in the straw. 
The iron was determined gravimetrically in every case and the manga¬ 
nese colorimetrically. The variation in the iron found is great if calcu¬ 
lated on the minimum Amount found; still the difference between the 
